Peter Sarsgaard peers into the webcam, half-man, half-beard. “I’m in the Kenny Rogers camp right now,” says the 50-year-old actor. “I look like a dropout. Whenever I’m not working, I feel like I’m growing hair in case I need it for the next movie.” His sleepy grin matches the rest of him: bed head, bed eyes, bed voice. It is this apparent languor that makes his glinting wit and flashes of cruelty stand out sharply on screen. He can be creep, charmer or both. “I don’t tell myself I’m the antagonist or the protagonist,” he says. “They can figure that out later.” He has played, among other things, a magazine editor who unpicks his colleague’s lies (Shattered Glass), a suave adulterer (An Education) and a transphobic killer (Boys Don’t Cry). His wife, Maggie Gyllenhaal, with whom he has two children, recently directed him in The Lost Daughter as a professor who falls for a married academic, played by Jessie Buckley. “I was nervous, because I wanted to do a good job in her movie,” he says. “I didn’t want people to say: ‘Too bad she cast her husband as the object of desire, because that doesn’t make any sense.’” No one did. Although Sarsgaard has only a few minutes to persuade us that a woman would leave her family for him, he is convincingly shrewd, seductive and ravenous. His tendency to seem half‑asleep and harmless until – snap! – he has you in his teeth, like a Venus flytrap, serves him well in the world of The Batman. Robert Pattinson plays the caped vigilante, while Sarsgaard is Gil Coulson, the shady, shaven-headed district attorney of Gotham City. “Gil is leading a double life,” he says. “He is protective of his family, but he’s involved in some things that are not legit.” The mix of sweet and sour appeals. “It creates more conflict. What if the biopic of Donald Trump showed how he made a damn good cherry pie on Thanksgiving, and sang songs with his family, but then he did all this other stuff?” While filming The Batman, he marvelled at Colin Farrell, who was unrecognisable beneath the Penguin’s prosthetics. “I said to Colin: ‘It’s a blast in there, isn’t it?’” Sarsgaard thought fondly of his own experience on The Green Lantern, in which he played a deranged scientist whose head swells up like a Macy’s Thanksgiving Day parade balloon. That maligned film gave him “the most variety I’ve ever had. Probably because I had this crazy 8lb [3.6kg] thing that took four hours to put on. You feel really liberated as an actor wearing a mask.” He is big on freedom and never discusses his creative choices before the camera rolls. “You need to give yourself agency as an actor. Don’t ask for a dancefloor – create one.” He is no superhero devotee, although his wife appeared in an earlier Batman film (The Dark Knight), while her brother Jake was the villain in Spider-Man: Far from Home. “So I’ve seen those,” he says. His viewing habits tend towards the esoteric. On one occasion, he was trusted by his high school friends to choose the evening’s entertainment and brought home Peter Greenaway’s transgressive arthouse thriller The Cook, the Thief, His Wife & Her Lover. “They had the beer ready. They were all set. Then afterwards, they were like: ‘Peter is not picking the movie any more.’” He giggles impishly. The surprise is that an actor who has been vocal about his scepticism about superhero films has made two of them. In 2009, he declared himself “a little suspicious” of them: “I’ve always wondered, if there were no money in playing superheroes … [whether] actors would still be as drawn to them.” How does he feel now? “The same way,” he says. “But there’s also the idea that we could do the most obscure, interesting thing in a basement somewhere – I joke with my wife that one day we’ll just do experimental theatre in some socialist country – and yet you want to share what you do with the largest number of people.” Have we reached saturation point with superhero films? “Probably,” he shrugs. “So, if you’re going to do one, you’d better be damn sure Matt Reeves is directing it.” Regardless of which film-maker is at the helm, the ubiquity of these blockbusters can only harm the kinds of films that Sarsgaard adores. When The Batman opens, it will swamp all available cinema screens; the latter-day equivalent of The Cook, the Thief, His Wife and Her Lover won’t get a look-in. “Right, right,” he says. Then a note of concern: “Do you think The Lost Daughter would be on the screen next to The Batman?” Still, an actor needs to eat. Sarsgaard does a better job than many of balancing superior schlock – he menaced Jodie Foster in Flightplan and was superb as the credulous father of a violent adoptive daughter in the horror movie Orphan – with searching, socially conscious fare such as the tragic, Soviet-era true story Mr Jones and the eco-thriller Night Moves, as well as TV series including The Looming Tower (about the events leading up to 9/11) and Dopesick (the US opioid crisis). Unease sets in if he is required to be himself. “Doing this is foreign to me,” he says, referring to the interview. Acting, though, he has always adored. “Since the moment I started, I’ve found comfort in it.” The roles themselves have rarely been soothing. For his film debut, he was murdered by Sean Penn in Dead Man Walking. “I wept during the audition. I think I wept because I wanted the part so badly.” Then he was John Malkovich’s son in The Man in the Iron Mask. “John asked me on set: ‘You know why they cast you, don’t you?’ I said: ‘No.’ He said: ‘It’s because you sound like me.’ I was like: ‘Oh. Bummer.’ I didn’t want that to be the reason.” Another high giggle slips out. It is true that they sound alike. But was Malkovich screwing with him? “Maybe. His whole sense of humour is based on that tension.” Has Sarsgaard done that to other actors? “Probably. I’ve been in situations where I couldn’t figure out how to work with another actor – and I’m not somebody who gives up – so I’ll encourage us to hang out together to find a connection so that we can at least drag something on to the screen.” Any examples? “Nuh-uh,” he says with a lopsided smile. “But it was worth asking.” His breakthrough came in 1999 with Boys Don’t Cry, although the shoot got off to a shaky start. After Sarsgaard’s first few takes as the real-life murderer John Lotter, the director Kimberly Peirce took him aside. “I thought I’d hired a man,” she said. “Turns out I’ve hired a pussy. So what are you going to do about it?” He gives a rueful look. “I was like: ‘Huh. OK. You wanna see a man?’ It struck me really hard. I’m not somebody who goes around like that character, lording it over people and being the sheriff in the room, so it was challenging for me to give myself permission to be a dick.” His newfound swagger spilled over when he was out with Chloë Sevigny and the rest of the cast at a “not-fancy” bar in Texas. “We ordered margaritas. Chloë took a sip and said: ‘Oh, it’s too sweet,’ and everyone sat there bummed‑out for a second. I picked up the tray of drinks, took it back to the bar and said: ‘These are awful. We want tequilas and we’re not paying for these.’ And I’m someone who never even returns corked wine.” How long did he carry that confidence with him? “A while. What stays with you as an actor after you’ve finished work are the things that are enjoyable. I don’t sit around trying to hold on to stuff from my work day. But things like that will stick.” He makes it sound like the body drawing nutrients out of food. “It definitely is. When you’re deciding whether to play a role, you ask questions such as: ‘Does this pose an interesting challenge?’ and: ‘Will it enable me to be a better actor, or to be wealthier?’ Hopefully, it checks several boxes. It’s not just: ‘Yay, I’m richer,’ or: ‘Yay, I’m doing experimental theatre in some country no one’s ever heard of.’” Unusually among actors, he enjoys watching himself on screen. “That’s not to say I could direct it while I act, but I know what I think works.” In a word: understatement. “I’d be like: ‘This moment’s good, but get rid of the part where I react to the big thing.’” Take The Man in the Iron Mask, in which his character is killed by a cannonball. “They’re waving a flamethrower in front of me to make this blinding heat and they want me to act like I can see the cannonball coming. Now, that is never going to look OK to me. What they wanted was this.” He widens his eyes in horror. “Whereas, if I were directing the movie, it would be more like this.” He stares blankly at the laptop screen. He doesn’t even blink. It reminds him of Liam Neeson’s advice on the set of Kathryn Bigelow’s K-19: The Widowmaker. Sarsgaard’s character had to embark on an apparent suicide mission to repair a nuclear reactor; Neeson suggested beforehand that he shouldn’t overdo the fear, since everyone in the audience would already be scared on his behalf. “That movie was a real acting lesson for me, to be around Harrison Ford and Liam and see how they approached all this technical stuff,” he says. “None of us knew what the hell we were saying: ‘Shut down No 3 generator, blah-blah-blah.’ Do you give up on that or do you try to find some meaning for yourself? Well, everything has meaning to Harrison Ford. I never saw him throw something away.” Not even his Russian accent? “No one wants to do an accent,” he protests. “Harrison and I did midwestern Russian. Liam did Irish Russian.” When I mention that Dennis Lim in the Village Voice described Ford’s performance as “acting without a nyet”, he roars with laughter. “Oh my God! That’s cruel. But awesome. Anyway, you could say the same about me in that movie.” One of Sarsgaard’s pieces of advice to young actors is: have a point of view. What is his? “I think movies have a responsibility to reflect something real about the concerns people face in their lives. If you can make that compelling, it’s going to be worthwhile to me. But I also like movies that are timeless, that exist outside social commentary.” Such as? “My wife’s movie. I was on a talkshow and they said: ‘Can you explain what’s happening before we show the clip?’ I was like: ‘Nuh-uh. I don’t think I can.’ That’s the sort of movie I love. One that you can’t set up.” He is right: The Lost Daughter is complex, enigmatic and resistant to precis. Rather like him. The Batman is released in Australia on 3 March and in the UK and the US on 4 March